Measurement of the distribution of m-xylene in rat tissues by head space gas chromatography.

An automated head space-gas chromatography (HS-GC) method was developed and evaluated for reliability in measurement of m-xylene in rat tissues. For tissue samples spiked with m-xylene (n = 2), the analytical precision was better than 12% relatives standard deviation (RSD) over the concentration range of 0.1 to ca 100 micrograms/g for liver and kidney, 0.1 to 170 micrograms/g for brain, 1.2 to 250 micrograms/g for fat, and 0.006 to 50 micrograms/mL for blood. For rats sacrificed immediately after an acute exposure to 1100 ppm of m-xylene, the relative tissue m-xylene concentrations were in the ascending order as follows: brain < or = blood < or = kidney < liver << fat. A precision of < 13% RSD was generally obtained for duplicate tissue samples from exposed animals, with m-xylene concentrations of about 10 micrograms/g of tissue.